FINANCIAL INSTRUMENTS (Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Hedge Accounting Basis Adjustment	$ 29
Fair Value Hedging
Derivative [Line Items]
Carrying Amount of Hedged Long-Term Debt	658	$ 0
Hedge Accounting Basis Adjustment	(29)	13
Remaining unamortized hedging adjustments on discontinued relationships	$ 5	$ 13

Debt Instrument, Fair Value Basis Adjustment Attributable to Hedged Debt

No definition available.

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Namespace Prefix:	dgx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective fair value hedge that is amortized upon discontinuation of the fair value hedge.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 25
-Name Accounting Standards Codification
-Section 35
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480295/815-25-35-9

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

+ Details

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- Details

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